The in-game "extra", sold at 3 energy a piece, offering only a few treasure boxes and sometimes a vitapod. I must say, it's far from worth its price.
3 Energy gives you:
A. a Vitapod which spawns regularly throughout the game + 2 (green!) treasure boxes.
B. an average of 6 (also green) treasure boxes.
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(A) is simply giving 1/3rd of a level-cost for something you find a lot more than 3 times in the actual level. Even more so, you don't get any monsters to kill for that 3 energy, so that increases the loss even more.
(B) is slightly better than (A), but still not worth the 3 energy. Throughout the level you find at least 10+ treasure boxes, along with a lot of monsters that drop crowns, heat, materials and an occasional item. So here again, not worth the energy cost at all.
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A few suggestions:
* Remove the vitapod energy door? Unless there are people who do find this Vitapod a big value-adder, then no need to pay attention to this suggestion.
* I have left out a (C). Some energy doors also have a Stranger behind them. Personally, these are the only energy doors I find worth the 3 energy. When I'm looking for that 1 unfindable recipe, an extra Stranger for only 3 energy is well worth it considering you only find ~1 stranger for every 40 energy-run to a Terminal. A suggestion here would be to add this type of energy door a lot more often!
* Replace the green treasure boxes with red ones, and increase the number you put there. Say, 10 or 15 in total? This might sound like a lot, but for those who have seen the core several times now.. Those 20 red treasure boxes are hardly worth the 10 energy you spend on that final gate.
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Any opinions on this issue?
i always open the energy doors since
a) i often tend to have leftover mist energy when i'm done playing for the day and don't care if it's worth it OR
b) i know i'm going to get all my energy back when the preview event is over so I have no qualms about spending it
BUT i'm sure point A doesn't apply to most people and B won't apply to me when the game goes to release, so in addition to the doors probably not being worth the energy now, they certainly won't be worth the energy in the future
here's another suggestion:
* if the 'use extra energy mid-level for more loot' exchange is considered important to how the game works, i say reduce the cost per door to a mere 1 energy so that the cost isn't as wildly disproportionate to the reward
(for a similar cost-reward discrepancy, see the autocannons -- they're fixed in place so they get maybe a couple kills, blah)
with the changes to vitapods from how they used to be, it's pretty likely that the vitapods from energy doors will rarely even be USABLE, much less worth the energy